Useful analysis/speculation; see the full post for more, e.g., on how Apple successfully introduces disruptive technologies.
It is my understanding that Apple and AT&T are planning a fall rollout for full 3G iPhone service, with technical trials already underway in certain AT&T markets. AT&T's (formerly Cingular's) 3G uses a technology called HSDPA (High-Speed Downlink Packet Access), which is a combination of GSM (Global System for Mobile communications) and EDGE (Enhanced Data rates for GSM Evolution). It provides average mobile data download connections between 400 kilobits per second (kbps) and 700 kbps. Not as fast as any of us would like, of course, but the new service will be 3-5 times faster than the current EDGE network alone, making your iPhone suddenly 3-5 times faster than it was before, right?
I think so. The question here is whether 3G is already built into the iPhones shipping now or whether it will require a new model? Given that it is coming so soon after the iPhone introduction, I can't believe that even Steve would make us buy new phones. It is very likely that a firmware upgrade will awaken the 3G within all you iPhone owners.